Single-Phase Direct Liquid Cooling Is Proven for the Next Decade of Ultra-Dense Compute

IEEE Spectrum and Wiley have released a white paper on single-phase direct liquid cooling, sponsored by CoolIT Systems. The paper covers how the approach manages the thermal demands of AI and high-performance computing and how it compares with two-phase and immersion cooling.

According to the paper's description, individual processors now exceed 1,000 watts and racks can dissipate more than 100 kilowatts, levels described as beyond what air cooling can practically remove. The paper states that single-phase direct liquid cooling circulates water or a water-glycol coolant through coldplates mounted directly on high-heat components. The coolant absorbs heat and carries it away in a closed loop to a coolant distribution unit. Because liquid stores far more heat than air and removes it faster, the paper says, the approach supports higher chip and rack densities within a smaller footprint.

Topics listed for the paper include why rising compute density has made heat a central design constraint; how semiconductors respond to excess heat through thermal throttling and why thermal margin is said to support higher performance and longer hardware life; why air cooling reaches a practical limit at high rack densities; how single-phase direct liquid cooling works at the chip and system levels; and expected growth in processor power and rack density and what it means for thermal design.

The document is a sponsored white paper presented by IEEE Spectrum and Wiley and sponsored by CoolIT Systems. Access requires registering a user profile on the hub and logging in.